This project is concerned with the evaluation of a variety of new and existing diagnostic techniques which have yet to be applied to biomedical diagnostic applications having particular relevance to dentistry. It is an extension of a more restricted project described last year which dealt with the development of quantitative methods for measuring factors believed to be associated with the myofacial pain dysfunction (MFPD) syndrome. Methods studied include photoplastic recording of strains associated with occlusal forces, computerized tomographic (CT) analysis of changes in size and shape of tissues of diagnostic interest, nuclear-medicine based techniques for tracking bone remodelling, and magnetic resonance imaging (MRI) as a noninvasive indicator of physiologic and pathologic changes in oral-facial tissues. Extensive measurements of occlusal stress patterns in patients known to be suffering from MFPD have yet to be analyzed statistically. Confirmatory data from CT analysis of cadaver specimens show that the maximum error in computed vs. actually measured volumes of the mandibular condyle is less than five percent with nominal values closer to one percent. Associated soft tissues such as the capsule of the temporal mandibular joint have been noninvasively displayed clearly for the first time with MRI. Preliminary findings using this modality also suggest that salivary gland activity may be monitored dynamically with no recognized biological risk or other side effects. Another new diagnostic modality being explored this year for the first time involves the use of a filtered optical system to colorimetrically detect the presence of oxygenated blood in the pulp chamber of vital teeth. Preliminary findings based on an analysis of red colored beads in the pulp chamber of extracted teeth appear promising.